Bulldozer



C. J. BATH Dec. 17, 1935.

BULLDOZER 2 Sheets$heet 1 Filed Jan. 22, 1931 Dec. 17, 1,935. c. J. BATH 2,024,754

- BULLDOZER Filed Jan. 22, 1931 2 sheets-sheet 2 IHIIIIIII I I ll IIIIIIIIIIIIIW A g) mun Patented Dec. 17, 1935 UNITED STATE.

AiEN'i' OFHQE BULLDOZER Application January 22, 1931, Serial No. 510,401

3 Claims. (Cl.-16486) This invention relates to machine tools of the punch press type having a reciprocable slide adapted to perform shearing or forming operations, and as its principal object aims to provide an improved machine of this kind.

Another object of this invention is to provide a machine of the kind mentioned having a novel form of frame construction.

Another object of this invention is to provide a machine of the kind mentioned. having a frame composed of elements formed of rolled stock and secured together by welding.

A further object of this invention is to provide a machine tool of the punch press type having a slide of novel construction.

Other objects and advantages of this invention will be apparent from the following description when taken in conjunction with the accompanying sheets of drawings, in which:

Figure 1 is a side elevation of a machine embodying my invention;

Fig. 2 is an end elevation thereof;

Fig. 3 is a top plan view of the same machine;

Fig. 4 is a transverse sectional view taken on line 44 of Fig. 1; and

Fig. 5 is a partial sectional view on an enlarged scale showing the slide bearing and guiding means.

Machine tools of the punch press type, as heretofore, constructed, have been provided with frames made of cast metal. When the pieces of work to be operated upon are large, or where the character of the work is such as to require great pressure, the frame castings for such machines must be extremely large and heavy in order to have the requisite strength. According- 1y, machines of this type having cast frames are always extremely bulky and heavy and cover considerable floor space. Moreover, because of the low tensile strength of cast metal, the frame members of such machines, which are made of this material, are frequently broken and must be replaced, usually requiring large and expensive repair parts, and involving costly delays in production operations. To overcome these disadvantages, I have devised a machine tool having frame elements which are formed of rolled stock and which are secured together by welding. In the drawings I have shown one machine embodying the principle of my invention, but before proceeding with a detailed description thereof, it should be understood that my invention may be embodied in various machines of this kind.

As shown in the drawings, the machine tool of my invention comprises in general a frame it, a

reciprocable slide M adapted to carry a movable die member (not shown), and gearing for actuating the slide.

Ihe frame of this machine constitutes an important feature of my invention, and, according- 5 1y, will be described in considerable detail. This frame is provided with a pair of similarly shaped side members or elements it formed from comparatively thick plates of commercial rolled steel and held in spaced substantially parallel assembled relation by transversely extending vertical connecting members 53. These connecting members are also formed from rolled steel plate, and are preferably secured to the side elements by having their ends securely welded thereto. In forming the side elements of the frame, the rolled stock is cut to the appropriate shape for the desired machine. In this instance, they are so shaped as to provide integral extensions M at one end for supporting the slide actuating gearing, and to provide integral extensions l5 at the opposite end which constitute abutment means adapted to hold a stationary die member (not shown) for cooperation with the movable die member of the reciprocable slide I l In addition to the transversely extending vertical members it for connecting the side elements of the frame,

I provide a. horizontally disposed connecting member it which is made of rolled plate and which extends transversely between the side e1e- 3O ments adjacent their integral extensions 55. The ends of this connecting member are secured to the side elements by being welded thereto, and a longitudinal edge of this member may be Welded to a longitudinal edge portion of an adjacent vertical connecting member It. In this position and when secured in place in this manner, the connecting member l6 materially reenforces and strengthens the frame against breakage, particularly the extensions 85 against which the pressure of the slide is exerted.

When in assembled position, the side elements stand on edge in substantially parallel relation, as shown in the drawings. Intermediate the integral end extensions i i and Hi, I provide bearing plate members ll which are formed of rolled stock, and are welded to the upper edges of the plates forming the side elements, so as to provide bearing means upon which the slide may be moved. At one end of these bearin plate members, portions l8 thereof are bent to a substantially right angle position and are welded to the extensions it so as to provide supporting surfaces upon which a work platen or stationary die member may be mounted. If desired, the supporting 5 portions 18 may be thickened and reenforced by welding the blocks l9 thereto. For holding the work platen or stationary die member in place, screws 20 may be arranged to extend through the extensions I 8 and the blocks I9.

At the opposite end of the bearing plate members l1, these members are curved upwardly to provide the end portions I3 which are in substantially parallel relation with the portions 58 and are secured to the extensions M. For reenforcing the frame at that point thereof which is known as the throat, or, in other words, adjacent a the upwardly curved portions I8, I provide the angularly disposed plate members l9 and shown in Fig. 1. These plate members extend in divergentrelation from the junction of the end portions l8 with the intermediate portions of the bearing plate members I? and are secured to the extensions I4. It will be seen from the structure thus far described that I have provided a gap-type frame made of welded structural members which are so arranged that they provide adequate strength at the ends of the gap. Along the edges of the side elements opposite the bearing plates [1, I provide the stringers or plate memberslii, which are formed from rolled stock and are welded to-the lower edges of the side elements to reenr the main shaft. Connecting rods 26, having one end thereof pivoted tothe crank pins 25 and their other ends pivoted to the slide shaft or bar 27, operabl y connect the slide with the main gears.

The shaft 22 and the main gears secured thereto are driven by the main pinions 28 which'are secured to the countershaft 29 adjacent opposite ends thereof. This countershaft also extends through the extensions 14 on the side elements of the frame, and is journaled in bearings as which are mounted on these extensions. An intermediate driving gear 3|, which is secured to the countershaft, is driven by the 'pinion32 of the drive shaft 33. This drive shaft is journaled in bearings '34 mounted upon the extensions I4, and is provided with a suitable clutch, such as the friction clutch 35, for establishing a driving connection between this shaft and the pulley 35. This pulley is j ournaled on the drive shaft and is driven by the electric motor 31 by means of a suitable belt 38. Control handles 39, which are operably [connected with the clutch by means of the lever 40, afford a means for connecting and disconnecting the drive shaft with'the drive pulley 36 to thereby control the operation of the machine. 7

plate 4! of rolled stock forms the working face of e ,the slide and is preferably provided with'dovetail slots 42 for attaching the movabledie member. A

horizontally disposed plate "or slab 43 of rolled stock .forms'the back of the slide and is welded to the plate 4|. A transverse arch member at formed of rolled stock is disposed opposite the plate 4i and is welded directly to the back plate 43. At its ends and at intermediate points this arch member is Welded, respectively, to the end ribs 45 and the intermediate ribs 45 which, in turn are welded to the back plate s3 and to the plate 5 l. The slide shaft or bar 21, to the ends of which the connecting rods 24 are pivoted, extends transversely through openings in the ribs 45 and 46, and is held against turning by being welded to these ribs and tothe back plate 43. The slide may be supported directly upon the plate members if of the frame elements, but I prefer to provide hardened face plates which are secured to the members l! and form bearing surfaces for the slide.

It will be noted that, as shown in Figs. 4 and 5, the adjacent edges of the plate members I! are undercut or oppositely inclined, and are engaged by gibs or'guide' members which are secured to the slide and which have similarly inclined faces. These guide members are preferably secured to the slide body by'means of bolts #8 and are adapted to be adjusted laterally with respect to the undercut edges of the members 51, by means of set screws 55. These set-screws are arranged to extend through lugs or bars 5! depending from the "under surface of the back plate of the slide,

and are preferably provided with lock nuts 3 for securing them in place when the desired adjustment of the guide members 48 has been made. In this location, the guide members are readily accessible for adjustment and at the same time are protected against damage and shielded against entry of foreign material by the back plate43 of the slide; e

For mounting the electric motor 3'! which drives 7 the clutch pulley 36 to operate the'machine, I

provide a motor baseor supporting plate 53 which is located between and is protected by the integral extensions of the frame elements. To-permit adjustment of the tension of the driving belt, I prefer to attach the motor base to its supporting means so that the inclination of the plane of this base may be varied in a well-known manner.

openings in the side elements. These sleeves have 7 internal diameters somewhat larger than the external diameters of the shafts which they are to accommodate, and at assembly of the machine the sleeves are preferably fitted with bushings to support the shafts, but, if desired, the sleeves may be babbitted to provide them with bearing surfaces for the shafts. To reenforce these bearings, I prefer to provide the ribs 54 shown in the draw ings, which may be welded to the sleeves and to the frame elements.

It should be noted that with the frame construction and the arrangement of gearing which I have provided, the clutch, the driving motor,

and other parts are located between the extensions l4 so that by fitting screens or plate members 55 to the edges the frame elements this mechanism can be easily and adequately housed actuating gearing which are outside of the space between the frame elements, suitable guards or cover members 56 may be provided.

It will be readily understood from the foregoing description that I have provided a machine tool having a novel form of frame construction. Machine tools embodying this frame construction are comparatively light in weight, but, because of the high tensile strength of the rolled steel stock from which the frames are constructed, the machines are capable of exerting great pressures upon the work without danger of cracking or breaking of the frame elements. It will be seen also, that in the machine which I have devised, much of the slide actuating mechanism and gearing is housed between the extensions of the frame elements where it cannot cause injury to workmen operating the machine, and where it is protected from damage and can easily be shielded against the entry of foreign matter.

While I have illustrated and described the device of my invention in a detailed manner, it should be understood, however, that I do not intend to limit myself to the precise details and arrangements of parts illustrated and described, but regard my invention as includingsuch changes and modifications as do not involve a deparature from the spirit of the invention and the scope of the appended claims.

Having thus described my invention, I claim:

1. A machine tool of the character described, comprising spaced frame elements formed from rolled stock, connecting means for said elements,

said slide and a stationary platen or die, and plate members secured to said side elements intermediate said extensions to provide bearing means for said slide, said plate members having angularly disposed end portions secured to said extensions.

3. A frame for a machine tool of the type hav- V ing a reciprocable slide, comprising spaced side elements formed from rolled stock, connecting means extending between said side elements, in-

tegral extensions at opposite ends of said side elements forming the ends of a gap and forming means for supporting, respectively, gearing for actuating said slide and a stationary platen or die, plate members secured to said side elements intermediate said extensions to provide bearing Y means for said slide, said plate members having angularly disposed end portions secured to said extensions, and means for reenforcing said side elements adjacent said angularly disposed end portions.

CYRIL J. BATH. 

